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arXiv · 1604.03571

Real time confinement following a quantum quench to a non-integrable model

Abstract

Light cone spreading of correlations and entanglement is a key feature of the non-equilibrium quench dynamics of many-body quantum systems. First proposed theoretically, it has been experimentally revealed in cold-atomic gases and it is expected to be a generic characteristic of any quench in systems with short-range interactions and no disorder. Conversely, here we propose a mechanism that, through confinement of the elementary excitations, strongly suppresses the light-cone spreading. Confinement is a celebrated concept in particle physics, but it also exists in condensed matter systems, most notably in one spatial dimension where it has been experimentally observed. Our results are obtained for the Ising spin chain with transverse and longitudinal magnetic field, but the proposed mechanism is of general validity since it is based on the sole concept of confinement and it should be easily observed in cold atom experiments.

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M. Kormos, M. Collura, G. Takács, P. Calabrese. 2016-04-12. Real time confinement following a quantum quench to a non-integrable model. https://doi.org/10.1038/nphys3934

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